English verb conjugation
SHOULD UNDERUSE

Regular verb: underuse - underused - underused

Affirmation

Simple form	V-ing form
I should underuse you should underuse he should underuse we should underuse you should underuse they should underuse	I should be underusing you should be underusing he should be underusing we should be underusing you should be underusing they should be underusing
Perfect	V-ing perfect
I should have underused you should have underused he should have underused we should have underused you should have underused they should have underused	I should have been underusing you should have been underusing he should have been underusing we should have been underusing you should have been underusing they should have been underusing

Negation

Simple form	V-ing form
I should not underuse you should not underuse he should not underuse we should not underuse you should not underuse they should not underuse	I should not be underusing you should not be underusing he should not be underusing we should not be underusing you should not be underusing they should not be underusing
Perfect	V-ing perfect
I should not have underused you should not have underused he should not have underused we should not have underused you should not have underused they should not have underused	I should not have been underusing you should not have been underusing he should not have been underusing we should not have been underusing you should not have been underusing they should not have been underusing

Interrogative form

Simple form	V-ing form
should I underuse? should you underuse? should he underuse? should we underuse? should you underuse? should they underuse?	should I be underusing? should you be underusing? should he be underusing? should we be underusing? should you be underusing? should they be underusing?
Perfect	V-ing perfect
should I have underused? should you have underused? should he have underused? should we have underused? should you have underused? should they have underused?	should I have been underusing? should you have been underusing? should he have been underusing? should we have been underusing? should you have been underusing? should they have been underusing?

Interro-negative form

Simple form	V-ing form
should I not underuse? should you not underuse? should he not underuse? should we not underuse? should you not underuse? should they not underuse?	should I not be underusing? should you not be underusing? should he not be underusing? should we not be underusing? should you not be underusing? should they not be underusing?
Perfect	V-ing perfect
should I not have underused? should you not have underused? should he not have underused? should we not have underused? should you not have underused? should they not have underused?	should I not have been underusing? should you not have been underusing? should he not have been underusing? should we not have been underusing? should you not have been underusing? should they not have been underusing?